1. Field of the Invention
The system of the present invention relates to bulk bags. More particularly the present invention relates to the attachment of lifting loops of bulk bags, along either the bag corners or along the central portion of each side wall in combination with a bottleneck bag feature for allowing greater and more secure stackability of the filled bags.
2. General Background
Bulk bags have been in use for over 30 years in the package industry. The original concept of bulk bags was to create a package that can carry ½ ton to 2 tons of dry flowable products by mechanical means from one factory to another.
While every bag has been designed to safely carry the weight upon four lifting loops built into the top of the bag, the vast majority of bags are shipped upon wood pallets. This has increased the cost of using these bags significantly.
Essentially this has been done in order to speed up the process of picking up the bag for transport. The loops on the top of bulk bags are undependable in position and too small to allow forklift drivers quick and easy access. Almost all current bulk bag designs require the forklift operator to stop and physically place the loops onto the forklift tines or, alternatively, have a second person standing by to place the loops as the operator drives forward.
In the issue of stacking and unstacking bulk bags more safely, the prior art basically reduces all the lifting safety into equal amounts in each corner. That amount is basically ¼ of the total. This is true because each loop is only attached to ¼ of the lifting power of the bag.
In the unstacking process in the current state of the art, it is very difficult for the fork lift operator to see all four loops. The higher the stack, the greater the vision impairment and the greater the chance that the operator will fail to get all four loops. This problem is further aggravated by the fact that the two rear loops are horizontally 36 inches behind the front loops. The front of an elevated bag can completely hide the fork operator's vision of those rear positioned loops.
When this is added to the small target that is also poorly supported and may not be standing up at all, it is easy to see that this method of retrieval is discouraging and unworkable in the present art.
As an alternative to wood pallets, there are two very important features which are addressed. The first is the manner in which the filled bulk bag, which may weigh two or more tons, is lifted from one point to another. The second important feature is whether the filled bulk bags may be stacked firmly and securely upon one other so as to allow more filled bags to be placed in a storage or transport space.
There have been many patents granted on these features of bulk bags over the years. In fact, the present inventor has numerous patents relating to bulk bags, and currently has a patent pending on an improved means for filling a bulk bag so that the bag remains stationary, and the side walls remain, completely upright, as the filled bags are stacked upon one another. However, as is usually the case, there is room for improvement in the combination of the lifting loop attachment coupled with the bottleneck feature of the bag so as to have both easy transport of the filled bags, and secure stackability of the bags, which this invention addresses.
The current invention resolves this issue in a unique manner. Each lifting loop has been designed to reach across large portions of the bag instead of starting and stopping within a single corner of the bag. This provides the fork lift operator with a very large target for easy engagement of the lifting loops.